A stolen smartphone was able to do its own detective work — by taking a photo of the man who might have snatched it.

Police want to talk to this “person of interest” (pictured), who was photographed holding a phone stolen from a man in the Inwood section of Manhattan, cops said.

The victim was inside a pedestrian walkway at the 190th Street A-train station on Sunday when three men passed by him, cops said.

One suspect covered the 34-year-old victim’s eyes, while two accomplices rifled through his pockets, taking $10 and an HTC One phone, police said.

They fled using the station’s Broadway exit, cops said. The victim, through, wasn’t about to part easily with his device.

First he called 911. Then he activated an app called Cerberus, which he’d already downloaded for about $4.

Cerberus allows people to locate and track missing phones — and to activate the camera remotely.

The app can even “start a loud alarm, even if the device is set to silent mode,” according to its Web site.

The victim waited until he saw the face of the person who had his phone — at which point he shot a secret photo and handed it over to officials, cops said.

“It helps when you have an actual picture,” said one law-enforcement source. “It’s an aid.”

The person photographed may not be the actual thief — but police believe he can at least lead them to the perps. Anyone with information about this incident is asked to anonymously call Crime Stoppers at (800) 577-TIPS, police said.

“We don’t know if this is one of the three because [the victim] may not have gotten the best look at them — but we definitely want to talk to the person who has his phone,” another police source said.

Cops believe the person in the photo is about 19 years old, and is wearing a blue shirt with a white t-shirt underneath.

Smartphone robberies have become a scourge in the subways in recent years, according to crime statistics.

Apple products are the prime target.

The number of thefts of iPhones, iPods, iPads and related gizmos was up about 40 percent toward the end of 2012, according to city stats.

There were 11,447 thefts of Apple products between January and September of 2012.